Study: Policies Reducing Lead Poisoning Have Academic Benefits, Too
High lead levels in children are connected to lower academic performance, and programs that reduced the rate of lead exposure and poisoning can also be tied to improved academic achievement, says a new Massachusetts study from the National Bureau of Economic Research.
The reduction in lead levels and improvement in test scores is evidence that strong public health policy—Massachusetts' lead laws are notably strong, and the state health department's Childhood Lead Poisoning Prevention Program, or CLPPP, has led to successful screening and education programs—can have positive impacts on education and on society, writes Jessica Wolpaw Reyes, an associate professor of economics at Amherst College.
Reyes looked at the Massachusetts Comprehensive Assessment System, or MCAS, scores of cohorts of 3rd and 4th graders attending elementary school between 2000-09 and childhood lead levels for the same groups of students from the Massachusetts CLPPP. Groups of children with higher levels of blood-lead exposure were likely to do worse on the tests, and as blood-lead levels dropped, student achievement improved. "Over the time period under consideration, reductions in lead have yielded a drop of 1 to 2 percentage points in the share of children scoring unsatisfactory on the MCAS test," the paper says. A decline in the gap in rates of high lead exposure between higher- and lower-income students was also connected to a 1 percentage-point reduction in the student-performance gap between those groups of students.
Reyes writes that her data shows the social benefits of programs aimed at reducing lead, but she also suggests lead-reduction has implications for education policymakers as well as public health officials. "Policymakers concerned with improving academic outcomes may want to broaden their view, looking beyond traditional education policies to consider other environmental and public health policies that can have considerable impacts on children's cognitive and social development," Reyes writes.
This is an argument I heard regularly while researching this recent story on research and programs addressing lead poisoning and contamination in Detroit. Researchers there were able to get student-level test information and connect it to health department data on blood-lead levels. (Here's the Memorandum of Understanding, if you're interested.)In a still-unpublished paper, they also conclude that there is a strong tie between academic performance and students' blood-lead levels. Randall Raymond, a GIS specialist at the Detroit schools who was involved in the research, said educators should acknowledge that lead is a factor in the achievement gap and then figure out how to help those students. "It's not just poverty that's a problem—it's environmental health issues we're confronted with," he said.
Lead exposure has long been acknowledged to hurt cognitive abilities (and also to be tied to involvement in the criminal justice system), and recent research has made the case that even low levels of lead exposure are not safe. The U.S. Department of Housing and Urban Development, or HUD, provides local governments with funds to reduce lead paint risks in housing, while the Centers for Disease Control and Prevention, or CDC, has funded programs like CLPPP aimed at surveillance, education, and abatement. Rates of lead exposure have declined dramatically nationwide—not just in Massachusetts. But research continues to show that many children—and, disproportionately, low-income and African-American children—still suffer from its effects.
The CDC's funding for programs like the CLPPP was recently cut dramatically, which is not addressed in the NBER paper. Mary Sue Schottenfels, the executive director of CLEARCorps/Detroit, an advocacy group that works to educate and aid Detroit families affected by lead, cautioned against thinking that the problem of lead has been solved, despite the gains demonstrated in research like Reyes'. "It's just a shame we can't just finish this...one lead-poisoned kid is too many," she said.
Reyes comes to the same conclusion in her paper: "These policies and their impacts are certainly of historical interest, but it would be a mistake to think they exist only in the past." Reyes plans to continue her research by looking at individual-level data and conducting a more thorough cost-benefit analysis of the state's lead programs.